Everyone wants clean energy. Hydrogen is one of the key elements which have a great potential to take a major role of clean energy for our life without CO2 emission in the near future. According to The Nikkei Asian Review, hydrogen is considered a green, next-generation energy source. Unlike fossil fuels, hydrogen does not emit carbon dioxide: It only produces water when it is burned. It is the lightest of all elements; its calorific value per unit weight is 2.7 times higher than gasoline.Japan's Toyota Motor unveiled a fuel-cell vehicle, which runs on hydrogen, at the end of last year. Honda Motor plans to introduce a similar vehicle during fiscal 2015, which begins next month. Kawasaki Heavy Industries and Mitsubishi Heavy Industries are developing hydrogen power generation technologies.According to the article (from The Nikkei Asian Review), hydrogen will be in short supply in 2020 (in Japan) or later if no measures are taken. Therefore, it is very important to secure the stable supply of hydrogen.To solve this problem, Kawasaki Heavy is leading a project to produce a large amount of hydrogen by gasifying lignite, a cheap and low-quality coal produced in southeast Australia, and bring it to Japan. The company aims to start operations on a trial basis in 2020.Kawasaki Heavy also intends to lower hydrogen sales prices, another challenge facing the Japanese hydrogen industry. "We want to halve the current wholesale price of hydrogen to roughly 30 yen ($0.25) per cubic meter in 2025," says Motohiko Nishimura, senior manager of the Hydrogen Project Department.A major Japanese electrical machinery maker Toshiba and the city of Kawasaki jointly conducted demonstration tests this year to produce emission-free hydrogen from renewable energy sources.They will store energy produced by solar power in batteries and produce hydrogen by electrolysing water as needed. The produced hydrogen will be supplied to a fuel cell to make electricity and hot water.Metawater, Japan's largest supplier of waste water treatment system, will build a plant to obtain hydrogen by reforming biogas made from sewage sludge and supply the resulting product to fuel cells.Ref:http://asia.nikkei.com/Tech-Science/Tech/The-lightest-element-faces-heavy-challenges